AAV mediated genome engineering with a bypass coagulation factor alleviates the bleeding phenotype in a murine model of hemophilia B.

It is crucial to develop a long-term therapy that targets hemophilia A and B, including inhibitor-positive patients. We have developed an Adeno-associated virus (AAV) based strategy to integrate the bypass coagulation factor, activated FVII (murine, mFVIIa) gene into the Rosa26 locus using Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/Cas9 mediated gene-editing. AAV vectors designed for expression of guide RNA (AAV8-gRNA), Cas9 (AAV2 neddylation mutant-Cas9), and mFVIIa (AAV8-mFVIIa) flanked by homology arms of the target locus were validated in vitro. Hemophilia B mice were administered with AAV carrying gRNA, Cas9 (1 × 1011 vgs/mouse), and mFVIIa with homology arms (2 × 1011 vgs/mouse) with appropriate controls. Functional rescue was documented with suitable coagulation assays at various time points. The data from the T7 endonuclease assay revealed a cleavage efficiency of 20-42 %. Further, DNA sequencing confirmed the targeted integration of mFVIIa into the safe-harbor Rosa26 locus. The prothrombin time (PT) assay revealed a significant reduction in PT in mice that received the gene-editing vectors (22 %), and a 13 % decline in mice that received only the AAV-FVIIa when compared to mock treated mice, 8 weeks after vector administration. Furthermore, FVIIa activity in mice that received triple gene-editing vectors was higher (122.5mIU/mL vs 28.8mIU/mL) than the mock group up to 15 weeks post vector administration. A hemostatic challenge by tail clip assay revealed that hemophilia B mice injected with only FVIIa or the gene-editing vectors had significant reduction in blood loss. In conclusion, AAV based gene-editing facilitates sustained expression of coagulation FVIIa and phenotypic rescue in hemophilia B mice.

Is CYP2C Haplotype Relevant for Efficacy and Bleeding Risk in Clopidogrel-Treated Patients?

A recently discovered haplotype-CYP2C:TG-determines the ultrarapid metabolism of several CYP2C19 substrates. The platelet inhibitor clopidogrel requires CYP2C19-mediated activation: the risk of ischemic events is increased in patients with a poor (PM) or intermediate (IM) CYP2C19 metabolizer phenotype (vs. normal, NM; rapid, RM; or ultrarapid, UM). We investigated whether the CYP2C:TG haplotype affected efficacy/bleeding risk in clopidogrel-treated patients. Adults (n = 283) treated with clopidogrel over 3-6 months were classified by CYP2C19 phenotype based on the CYP2C19*2*17 genotype, and based on the CYP2C19/CYP2C cluster genotype, and regarding carriage of the CYP2:TG haplotype, and were balanced on a number of covariates across the levels of phenotypes/haplotype carriage. Overall, 45 (15.9%) patients experienced ischemic events, and 49 (17.3%) experienced bleedings. By either classification, the incidence of ischemic events was similarly numerically higher in PM/IM patients (21.6%, 21.8%, respectively) than in mutually similar NM, RM, and UM patients (13.2-14.8%), whereas the incidence of bleeding events was numerically lower (13.1% vs. 16.6-20.5%). The incidence of ischemic events was similar in CYP2C:TG carries and non-carries (14.1% vs. 16.1%), whereas the incidence of bleedings appeared mildly lower in the former (14.9% vs. 20.1%). We observed no signal to suggest a major effect of the CYP2C19/CYP2C cluster genotype or CYP2C:TG haplotype on the clinical efficacy/safety of clopidogrel.

Gene polymorphism as a cause of hemorrhagic complications in patients with non-valvular atrial fibrillation treated with oral vitamin K-independent anticoagulants.

Atrial fibrillation (AF) accounts for 40% of all cardiac arrhythmias and is associated with a high risk of stroke and systemic thromboembolic complications. Dabigatran, rivaroxaban, apixaban, and edoxaban are direct oral anticoagulants (DOACs) that have been proven to prevent stroke in patients with non-valvular AF. This review summarizes the pharmacokinetics, pharmacodynamics, and drug interactions of DOACs, as well as new data from pharmacogenetic studies of these drugs. This review is aimed at analyzing the scientific literature on the gene polymorphisms involved in the metabolism of DOACs. We searched PubMed, Cochrane, Google Scholar, and CyberLeninka (Russian version) databases with keywords: 'dabigatran', 'apixaban', 'rivaroxaban', 'edoxaban', 'gene polymorphism', 'pharmacogenetics', 'ABCB1', 'CES1', 'SULT1A', 'ABCG2', and 'CYP3A4'. The articles referred for this review include (1) full-text articles; (2) study design with meta-analysis, an observational study in patients taking DOAC; and (3) data on the single-nucleotide polymorphisms and kinetic parameters of DOACs (plasma concentration), or a particular clinical outcome, published in English and Russian languages during the last 10 years. The ages of the patients ranged from 18 to 75 years. Out of 114 reviewed works, 24 were found eligible. As per the available pharmacogenomic data, polymorphisms affecting DOACs are different. This may aid in developing individual approaches to optimize DOAC pharmacotherapy to reduce the risk of hemorrhagic complications. However, large-scale population studies are required to determine the dosage of the new oral anticoagulants based on genotyping. Information on the genetic effects is limited owing to the lack of large-scale studies. Uncovering the mechanisms of the genetic basis of sensitivity to DOACs helps in developing personalized therapy based on patient-specific genetic variants and improves the efficacy and safety of DOACs in the general population.

Gene polymorphism as a cause of hemorrhagic complications in patients with non-valvular atrial fibrillation treated with oral vitamin K-independent anticoagulantsAtrial fibrillation (AF) accounts for 40% of all cardiac arrhythmias and is associated with a high risk of stroke and systemic thromboembolic complications. Dabigatran, rivaroxaban, apixaban, and edoxaban are direct oral anticoagulants (DOACs) that have been proven to prevent stroke in patients with non-valvular AF. This review summarizes the pharmacokinetics, pharmacodynamics, and drug interactions of DOACs, as well as new data from pharmacogenetic studies of these drugs.

Epigenetic regulation of H3K27me3 in laying hens with fatty liver hemorrhagic syndrome induced by high-energy and low-protein diets.

BACKGROUND: Fatty liver hemorrhagic syndrome (FLHS) in the modern poultry industry is primarily caused by nutrition. Despite encouraging progress on FLHS, the mechanism through which nutrition influences susceptibility to FLHS is still lacking in terms of epigenetics. RESULTS: In this study, we analyzed the genome-wide patterns of trimethylated lysine residue 27 of histone H3 (H3K27me3) enrichment by chromatin immunoprecipitation-sequencing (ChIP-seq), and examined its association with transcriptomes in healthy and FLHS hens. The study results indicated that H3K27me3 levels were increased in the FLHS hens on a genome-wide scale. Additionally, H3K27me3 was found to occupy the entire gene and the distant intergenic region, which may function as silencer-like regulatory elements. The analysis of transcription factor (TF) motifs in hypermethylated peaks has demonstrated that 23 TFs are involved in the regulation of liver metabolism and development. Transcriptomic analysis indicated that differentially expressed genes (DEGs) were enriched in fatty acid metabolism, amino acid, and carbohydrate metabolism. The hub gene identified from PPI network is fatty acid synthase (FASN). Combined ChIP-seq and transcriptome analysis revealed that the increased H3K27me3 and down-regulated genes have significant enrichment in the ECM-receptor interaction, tight junction, cell adhesion molecules, adherens junction, and TGF-beta signaling pathways. CONCLUSIONS: Overall, the trimethylation modification of H3K27 has been shown to have significant regulatory function in FLHS, mediating the expression of crucial genes associated with the ECM-receptor interaction pathway. This highlights the epigenetic mechanisms of H3K27me3 and provides insights into exploring core regulatory targets and nutritional regulation strategies in FLHS.

Gene Dosage of F5 c.3481C>T Stop-Codon (p.R1161Ter) Switches the Clinical Phenotype from Severe Thrombosis to Recurrent Haemorrhage: Novel Hypotheses for Readthrough Strategy.

Inherited defects in the genes of blood coagulation essentially express the severity of the clinical phenotype that is directly correlated to the number of mutated alleles of the candidate leader gene (e.g., heterozygote vs. homozygote) and of possible additional coinherited traits. The F5 gene, which codes for coagulation factor V (FV), plays a two-faced role in the coagulation cascade, exhibiting both procoagulant and anticoagulant functions. Thus, defects in this gene can be predisposed to either bleeding or thrombosis. A Sanger sequence analysis detected a premature stop-codon in exon 13 of the F5 gene (c.3481C>T; p.R1161Ter) in several members of a family characterised by low circulating FV levels and contrasting clinical phenotypes. The propositus, a 29 y.o. male affected by recurrent haemorrhages, was homozygous for the F5 stop-codon and for the F5 c.1691G>A (p.R506Q; FV-Leiden) inherited from the heterozygous parents, which is suggestive of combined cis-segregation. The homozygous condition of the stop-codon completely abolished the F5 gene expression in the propositus (FV:Ag < 1%; FV:C < 1%; assessed by ELISA and PT-based one-stage clotting assay respectively), removing, in turn, any chance for FV-Leiden to act as a prothrombotic molecule. His father (57 y.o.), characterised by severe recurrent venous thromboses, underwent a complete molecular thrombophilic screening, revealing a heterozygous F2 G20210A defect, while his mother (56 y.o.), who was negative for further common coagulation defects, reported fully asymptomatic anamnesis. To dissect these conflicting phenotypes, we performed the ProC®Global (Siemens Helthineers) coagulation test aimed at assessing the global pro- and anticoagulant balance of each family member, investigating the responses to the activated protein C (APC) by means of an APC-sensitivity ratio (APC-sr). The propositus had an unexpectedly poor response to APC (APC-sr: 1.09; n.v. > 2.25), and his father and mother had an APC-sr of 1.5 and 2.0, respectively. Although ProC®Global prevalently detects the anticoagulant side of FV, the exceptionally low APC-sr of the propositus and his discordant severe-moderate haemorrhagic phenotype could suggest a residual expression of mutated FV p.506QQ through a natural readthrough or possible alternative splicing mechanisms. The coagulation pathway may be physiologically rebalanced through natural and induced strategies, and the described insights might be able to track the design of novel treatment approaches and rebalancing molecules.

Common P-glycoprotein (ABCB1) polymorphisms do not seem to be associated with the risk of rivaroxaban-related bleeding events: Preliminary data.

Introduction: Considering conflicting previous reports, we aimed to evaluate whether the common ABCB1 polymorphisms (rs1128503, rs2032582, rs1045642, rs4148738) affected the risk of bleeding in rivaroxaban-treated patients. Materials and methods: We report preliminary data from a larger nested case-control study. Consecutive adults started on rivaroxaban for any indication requiring > 6 months of treatment were followed-up to one year. Patients who experienced major or non-major clinically relevant bleeding during the initial 6 months were considered cases, whereas subjects free of bleeding over > 6 months were controls. The polymorphisms of interest (rs1128503, rs2032582, rs1045642, rs4148738) were in a strong linkage disequilibrium, hence patients were classified regarding the "load" of variant alleles: 0-2, 3-5 or 6-8. The three subsets were balanced regarding a range of demographic, comorbidity, comedication and genetic characteristics. A logistic model was fitted to probability of bleeding. Results: There were 60 cases and 220 controls. Raw proportions of cases were similar across the subsets with increasing number of ABCB1 variant alleles (0-2, N = 85; 3-6, N = 133; 6-8, N = 62): 22.4%, 21.8%, and 19.4%, respectively. Fully adjusted probabilities of bleeding were also similar across the subsets: 22.9%, 27.5% and 17.7%, respectively. No trend was observed (linear, t = -0.63, df = 273, P = 0.529; quadratic, t = -1.10, df = 273, P = 0.272). Of the 15 identified haplotypes, the completely variant (c.1236T_c.2677T(A)_c.3435T_c.2482-2236A) (40.7%) and completely wild-type (C_G_C_G) (39.5%) haplotypes prevailed, and had a closely similar prevalence of cases: 21.1% vs. 23.1%, respectively. Conclusions: The evaluated common ABCB1 polymorphisms do not seem to affect the risk of early bleeding in patients started on rivaroxaban.

Association between CYP2C9 and VKORC1 genetic polymorphisms and efficacy and safety of warfarin in Chinese patients.

OBJECTIVES: Genetic variation has been a major contributor to interindividual variability of warfarin dosage requirement. The specific genetic factors contributing to warfarin bleeding complications are largely unknown, particularly in Chinese patients. In this study, 896 Chinese patients were enrolled to explore the effect of CYP2C9 and VKORC1 genetic variations on both the efficacy and safety of warfarin therapy. METHODS AND RESULTS: Univariate analyses unveiled significant associations between two specific single nucleotide polymorphisms rs1057910 in CYP2C9 and rs9923231 in VKORC1 and stable warfarin dosage ( P  < 0.001). Further, employing multivariate logistic regression analysis adjusted for age, sex and height, the investigation revealed that patients harboring at least one variant allele in CYP2C9 exhibited a heightened risk of bleeding events compared to those with the wild-type genotype (odds ratio = 2.16, P  = 0.04). Moreover, a meta-analysis conducted to consolidate findings confirmed the associations of both CYP2C9 (rs1057910) and VKORC1 (rs9923231) with stable warfarin dosage. Notably, CYP2C9 variant genotypes were significantly linked to an increased risk of hemorrhagic complications ( P  < 0.00001), VKORC1 did not demonstrate a similar association. CONCLUSION: The associations found between specific genetic variants and both stable warfarin dosage and bleeding risk might be the potential significance of gene detection in optimizing warfarin therapy for improving patient efficacy and safety.

Toward Genetic Testing of Rivaroxaban? Insights from a Systematic Review on the Role of Genetic Polymorphism in Rivaroxaban Therapy.

BACKGROUND: Investigations into the rivaroxaban response from the perspective of genetic variation have been relatively recent and wide in scope, whereas there is no consensus on the necessity of genetic testing of rivaroxaban. Thus, this systematic review aims to thoroughly evaluate the relationship between genetic polymorphisms and rivaroxaban outcomes. METHODS: The PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Chinese databases were searched to 23 October 2022. We included cohort studies reporting the pharmacogenetic correlation of rivaroxaban. Outcomes measured included efficacy (all-cause mortality, thromboembolic events and coagulation-related tests), safety (major bleeding, clinically relevant non-major bleeding [CRNMB] and any hemorrhage), and pharmacokinetic outcomes. A narrative synthesis was performed to summarize findings from individual studies according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the reporting guideline for Synthesis Without Meta-Analysis. RESULTS: A total of 12 studies published between 2019 and 2022 involving 1364 patients were included. Ten, one, and six studies focused on the ABCB1, ABCG2, and CYP gene polymorphisms, respectively. Pharmacokinetic outcomes accounted for the majority of the outcomes reported (n = 11), followed by efficacy (n = 5) [including prothrombin time (PT) or international normalized ratio (n = 3), platelet inhibition rate (PIR) or platelet reactivity units (PRUs; n = 1), thromboembolic events (n = 1)], and safety (n = 5) [including major bleeding (n = 2), CRNMB (n = 2), any hemorrhage (n = 1)]. For ABCB1 gene polymorphism, the relationship between PT and ABCB1 rs1045642 was inconsistent across studies, however there was no pharmacogenetic relationship with other efficacy outcomes. Safety associations were found in ABCB1 rs4148738 and major bleeding, ABCB1 rs4148738 and CRNMB, ABCB1 rs1045642 and CRNMB, and ABCB1 rs2032582 and hemorrhage. Pharmacokinetic results were inconsistent among studies. For ABCG2 gene polymorphism, no correlation was observed between ABCG2 rs2231142 and dose-adjusted trough concentration (Cmin/D). For CYP gene polymorphisms, PIR or PRUs have a relationship with CYP2C19 rs12248560, however bleeding or pharmacokinetic effects did not show similar results. CONCLUSIONS: Currently available data are insufficient to confirm the relationship between clinical or pharmacokinetic outcomes of rivaroxaban and gene polymorphisms. Proactive strategies are advised as a priority in clinical practice rather than detection of SNP genotyping. CLINICAL TRIALS REGISTRATION: PROSPERO registration number CRD42022347907.

Women and girls with inherited bleeding disorders: Focus on haemophilia carriers and heavy menstrual bleeding.

Raising awareness and improving recognition, accurate classification, and enhanced access to new treatments represent current key challenges for carriers of haemophilia. Women and girls carrying genes for haemophilia often experience significant bleeding and/or low factor levels. The bleeding associated with female haemophilia is frequently overlooked, has a weak correlation with factor levels, and manifests differently than in males, with heavy menstrual bleeding being a predominant symptom. Recent changes in terminology now allow the diagnosis of haemophilia in females with low factor levels and differentiate between symptomatic and asymptomatic carriers of the gene. Observations from real-world experiences and limited clinical trial data have highlighted the positive impact of various new haemophilia treatments for women and girls with clotting factor deficiencies. There is an urgent need for initiatives that increase their access to these treatments and encourage well-designed clinical trials focusing on female-specific outcomes. In women with inherited bleeding disorders, early recognition and optimal management of heavy menstrual bleeding are crucial. However, treatment options and guidance from high-quality clinical trials are currently insufficient. Menstrual health assessment should be a regular part of monitoring women and girls with inherited bleeding disorders throughout their lives, emphasizing the importance of gathering data to improve future management.

Impact of allele-selective silencing of von Willebrand factor in mice based on a single nucleotide allelic difference in von Willebrand factor.

INTRODUCTION: Von Willebrand factor (VWF) plays a pathophysiological role in hemostatic disorders. Partial inhibition of the VWF gene through small interfering RNA (siRNA)-mediated allele-selective silencing could be a promising therapeutic strategy. For von Willebrand disease, allele-selectively inhibiting dominant-negative VWF-alleles might ameliorate the phenotype. For thrombotic disorders, partial VWF reduction can lower thrombotic risk, while avoiding bleeding. Previously, we demonstrated the feasibility of Vwf-silencing in homozygous C57BL/6J (B6) or 129S1/SvImJ (129S) mice. The present study investigated allele-selective Vwf-silencing in a complex heterozygous setting of crossed B6 and 129S mice and its subsequent hemostatic impact. MATERIALS AND METHODS: Heterozygous B6.129S mice were treated with siRNAs targeting Vwf expressed from either B6- (siVwf.B6) or 129S-alleles (siVwf.129S). Plasma VWF and lung Vwf mRNA were determined. siVwf.B6-treated B6.129S mice were subjected to ferric chloride-induced mesenteric vessel thrombosis and tail-bleeding. RESULTS: In B6.129S mice, siVwf.B6 reduced Vwf mRNA of the targeted B6-allele by 72% vs. only 12% of the non-targeted 129S-allele (41% total mRNA reduction), lowering plasma VWF by 46%. Oppositely, siVwf.129S reduced Vwf mRNA by 45%, now selectively inhibiting the 129S-allele over the B6-allele (58% vs. 9%), decreasing plasma VWF by 43%. The allele-selective VWF reduction by siVwf.B6 coincided with decreased thrombus formation in mesenteric arterioles, without prolonging tail-bleeding times. CONCLUSIONS: This study demonstrates the feasibility of allele-selective Vwf-silencing in a heterozygous setting, achieving a controlled close to 50% reduction of plasma VWF. The observed thromboprotection and absence of prolonged bleeding times underline the potential of allele-selective Vwf-silencing as a therapeutic strategy in hemostatic disorders.

Efficacy and Safety of Adeno-Associated Virus-Based Clinical Gene Therapy for Hemophilia: A Systematic Review and Meta-Analysis.

Clinical trials of adeno-associated virus (AAV)-based gene therapy have made remarkable progress in recent years. We aimed to perform a systematic review and meta-analysis of the literature to assess the efficacy and safety of AAV-based gene therapy for hemophilia. We systematically searched the Web of Science, Embase, PubMed, and the Cochrane Database of Systematic Reviews databases, for clinical trials involving patients diagnosed with hemophilia and treated with AAV-mediated gene therapy. Data on the annualized bleeding rate (ABR), annualized infusion rate (AIR), the incidence of treatment-related adverse events (TRAEs), severe adverse events (SAEs), and alanine aminotransferase (ALT) elevation were extracted as our outcomes. A total of 12 articles from 11 clinical trials were selected from 868 articles for meta-analysis. Pooled analyses showed that AAV-based gene therapy in hemophilia patients reduced the number of bleeding events and the number of factor infusion events by an approximate average of 7 per year and 103 per year, respectively. Eighty percent, 18%, and 63% of hemophilia patients had elevated TRAE, SAE, and ALT levels, respectively. Moreover, subgroup analysis found a significant reduction in ABR and AIR 2-3 years after the therapy. Additional findings that were not pooled including coagulation factor activity are presented in the accompanying tables. Our analysis supported the efficacy and safety of AAV-mediated gene therapy for hemophilia, providing evidence for its application as a therapeutic option for widespread clinical use in hemophilia patients in the future.

Congenital fibrinogen disorders: a retrospective clinical and genetic analysis of the Prospective Rare Bleeding Disorders Database.

ABSTRACT: Congenital fibrinogen deficiency (CFD) is a rare bleeding disorder caused by mutations in FGA, FGB, and FGG. We sought to comprehensively characterize patients with CFD using PRO-RBDD (Prospective Rare Bleeding Disorders Database). Clinical phenotypes, laboratory, and genetic features were investigated using retrospective data from the PRO-RBDD. Patients were classified from asymptomatic to grade 3 based on their bleeding severity. In addition, FGA, FGB, and FGG were sequenced to find causative variants. A total of 166 CFD cases from 16 countries were included, of whom 123 (30 afibrinogenemia, 33 hypofibrinogenemia, 55 dysfibrinogenemia, and 5 hypodysfibrinogenemia) were well characterized. Considering the previously established factor activity and antigen level thresholds, bleeding severity was correctly identified in 58% of the cases. The rates of thrombotic events among afibrinogenemic and hypofibrinogenemic patients were relatively similar (11% and 10%, respectively) and surprisingly higher than in dysfibrinogenemic cases. The rate of spontaneous abortions among 68 pregnancies was 31%, including 86% in dysfibrinogenemic women and 14% with hypofibrinogenemia. Eighty-six patients received treatment (69 on-demand and/or 17 on prophylaxis), with fibrinogen concentrates being the most frequently used product. Genetic analysis was available for 91 cases and 41 distinct variants were identified. Hotspot variants (FGG, p.Arg301Cys/His and FGA, p.Arg35Cys/His) were present in 51% of dysfibrinogenemia. Obstetric complications were commonly observed in dysfibrinogenemia. This large multicenter study provided a comprehensive insight into the clinical, laboratory, and genetic history of patients with CFDs. We conclude that bleeding severity grades were in agreement with the established factor activity threshold in nearly half of the cases with quantitative defects.

Heterozygosity in factor XIII genes and the manifestation of mild inherited factor XIII deficiency.

BACKGROUND: The characterization of inherited mild factor XIII deficiency is more imprecise than its rare, inherited severe forms. It is known that heterozygosity at FXIII genetic loci results in mild FXIII deficiency, characterized by circulating FXIII activity levels ranging from 20% to 60%. There exists a gap in information on 1) how genetic heterozygosity renders clinical bleeding manifestations among these individuals and 2) the reversal of unexplained bleeding upon FXIII administration in mild FXIII-deficient individuals. OBJECTIVES: To assess the prevalence and burden of mild FXIII deficiency among the apparently healthy German-Caucasian population and correlate it with genetic heterozygosity at FXIII and fibrinogen gene loci. METHODS: Peripheral blood was collected from 752 donors selected from the general population with essentially no bleeding complications to ensure asymptomatic predisposition. These were assessed for FXIII and fibrinogen activity, and FXIII and fibrinogen genes were resequenced using next-generation sequencing. For comparison, a retrospective analysis was performed on a cohort of mild inherited FXIII deficiency patients referred to us. RESULTS: The prevalence of mild FXIII deficiency was high (∼0.8%) among the screened German-Caucasian population compared with its rare-severe forms. Although no new heterozygous missense variants were found, certain combinations were relatively dominant/prevalent among the mild FXIII-deficient individuals. CONCLUSION: This extensive, population-based quasi-experimental approach revealed that the burden of heterozygosity in FXIII and fibrinogen gene loci causes the clinical manifestation of inherited mild FXIII deficiency, resulting in ''unexplained bleeding'' upon provocation.

Impact of non-driver gene mutations on thrombo-haemorrhagic events in ET patients.

Risk-adapted therapy is recommended to prevent major clinical complications, such as thrombo-haemorrhagic events, in patients with essential thrombocythaemia (ET). In this study, we analysed the association between non-driver gene mutations and thrombo-haemorrhagic events in 579 patients with ET. ASXL1 and TP53 mutations were frequently identified in patients with ET complicated by thrombosis (22.7% and 23.1%, respectively), and the DNMT3A mutation was frequently identified in patients who experienced haemorrhage (15.2%). Multivariate analyses of thrombosis-free survival (TFS) revealed that ASXL1 and TP53 mutations are associated with thrombosis (hazard ratio [HR] = 3.140 and 3.752 respectively). Patients harbouring the ASXL1 or TP53 mutation had significantly worse TFS rates than those without mutation (p = 0.002 and p < 0.001 respectively). Furthermore, JAK2V617F-mutated patients with accompanying ASXL1 mutations showed significantly shorter TFS compared with those without ASXL1 mutations (p = 0.003). Multivariate analyses of haemorrhage-free survival (HFS) revealed that the DNMT3A mutation (HR = 2.784) is associated with haemorrhage. DNMT3A-mutated patients showed significantly shorter HFS than those without the mutation (p = 0.026). Non-driver gene mutations should be considered in treatment strategies and may provide important information for personalised treatment approaches.

Postmortem diagnosis of severe factor X deficiency in a fetus with intracranial hemorrhage resulting in intrauterine death.

In patients with severe congenital factor X deficiency, spontaneous intracranial hemorrhage (ICH) is particularly frequent in early childhood. We describe a case of fetal death at 26 weeks due to massive ICH. Gene panel analysis of postmortem samples revealed homozygosity for a pathologic F10 gene variant (c.1210T>C, p.Cys404Arg), which impedes correct folding of the catalytic serine protease domain and, therefore, causes a significant reduction in FX levels. The parents, not consanguineous but of the same ethnic community, were found to be heterozygous for this variant and did not have any personal or family history of abnormal bleeding. To the best of our knowledge, this is the first reported case of severe FX deficiency resulting in ICH diagnosed through postmortem genetic analysis. It illustrates the importance of exploring the etiology of fetal or neonatal ICH, which may impact future pregnancies, and the treatment of a potential coagulopathy in the child.

A new case of platelet-type von Willebrand disease supports the recent findings of gain-of-function GP1BA variants outside the C-terminal disulphide loop enhances affinity for von Willebrand factor.

Platelet-type von Willebrand disease (PT-VWD) is a rare autosomal dominant bleeding disorder characterized by an increased ristocetin-induced platelet aggregation (RIPA) and enhanced affinity of platelet glycoprotein Ibα (GPIbα) to von Willebrand factor (VWF). To date, only seven variants have been described with this gain-of-function effect, most of them located in the C-terminal disulphide loop of the VWF-binding domain of GPIbα. We herein describe a patient with moderate bleeding symptoms, mild thrombocytopenia and increased RIPA. By direct sequencing of GP1BA, a novel leucine-rich repeat heterozygous variant was identified (c.580C>T; predictably p.Leu194Phe), strongly suggestive as being the underlying cause for the PT-VWD phenotype of our patient.

The effects of pathogenic and likely pathogenic variants for inherited hemostasis disorders in 140 214 UK Biobank participants.

Rare genetic diseases affect millions, and identifying causal DNA variants is essential for patient care. Therefore, it is imperative to estimate the effect of each independent variant and improve their pathogenicity classification. Our study of 140 214 unrelated UK Biobank (UKB) participants found that each of them carries a median of 7 variants previously reported as pathogenic or likely pathogenic. We focused on 967 diagnostic-grade gene (DGG) variants for rare bleeding, thrombotic, and platelet disorders (BTPDs) observed in 12 367 UKB participants. By association analysis, for a subset of these variants, we estimated effect sizes for platelet count and volume, and odds ratios for bleeding and thrombosis. Variants causal of some autosomal recessive platelet disorders revealed phenotypic consequences in carriers. Loss-of-function variants in MPL, which cause chronic amegakaryocytic thrombocytopenia if biallelic, were unexpectedly associated with increased platelet counts in carriers. We also demonstrated that common variants identified by genome-wide association studies (GWAS) for platelet count or thrombosis risk may influence the penetrance of rare variants in BTPD DGGs on their associated hemostasis disorders. Network-propagation analysis applied to an interactome of 18 410 nodes and 571 917 edges showed that GWAS variants with large effect sizes are enriched in DGGs and their first-order interactors. Finally, we illustrate the modifying effect of polygenic scores for platelet count and thrombosis risk on disease severity in participants carrying rare variants in TUBB1 or PROC and PROS1, respectively. Our findings demonstrate the power of association analyses using large population datasets in improving pathogenicity classifications of rare variants.

Protective effects of genistein on the production performance and lipid metabolism disorders in laying hens with fatty liver hemorrhagic syndrome by activation of the GPER-AMPK signaling pathways.

The aim of this study was to evaluate the beneficial effects and potential mechanisms of genistein (GEN) on production performance impairments and lipid metabolism disorders in laying hens fed a high-energy and low-protein (HELP) diet. A total of 120 Hy-line Brown laying hens were fed with the standard diet and HELP diet supplemented with 0, 50, 100, and 200 mg/kg GEN for 80 d. The results showed that the declines in laying rate (P < 0.01), average egg weight (P < 0.01), and egg yield (P < 0.01), and the increase of the ratio of feed to egg (P < 0.01) induced by HELP diet were markedly improved by 100 and 200 mg/kg of GEN treatment in laying hens (P < 0.05). Moreover, the hepatic steatosis and increases of lipid contents (P < 0.01) in serum and liver caused by HELP diet were significantly alleviated by treatment with 100 and 200 mg/kg of GEN in laying hens (P < 0.05). The liver index and abdominal fat index of laying hens in the HELP group were higher than subjects in the control group (P < 0.01), which were evidently attenuated by dietary 50 to 200 mg/kg of GEN supplementation (P < 0.05). Dietary 100 and 200 mg/kg of GEN supplementation significantly reduced the upregulations of genes related to fatty acid transport and synthesis (P < 0.01) but enhanced the downregulations of genes associated with fatty acid oxidation (P < 0.01) caused by HELP in the liver of laying hens (P < 0.05). Importantly, 100 and 200 mg/kg of GEN supplementation markedly increased G protein-coupled estrogen receptor (GPER) mRNA and protein expression levels and activated the AMP-activated protein kinase (AMPK) signaling pathway in the liver of laying hens fed a HELP diet (P < 0.05). These data indicated that the protective effects of GEN against the decline of production performance and lipid metabolism disorders caused by HELP diet in laying hens may be related to the activation of the GPER-AMPK signaling pathways. These data not only provide compelling evidence for the protective effect of GEN against fatty liver hemorrhagic syndrome in laying hens but also provide the theoretical basis for GEN as an additive to alleviate metabolic disorders in poultry.

Fatty liver hemorrhagic syndrome (FLHS) is a nutritional and metabolic disease that seriously threatens the health and performance of laying hens, which is characterized by hepatic steatosis and lipid metabolism disorders. As an isoflavone phytoestrogen, genistein (GEN) exerts many beneficial functions, including alleviating lipid metabolism disorders and anti-inflammatory properties. However, further research is needed on the protective effect and potential mechanism of GEN on the FLHS in laying hens. Here, we found that GEN treatment improved liver injury and decline of production performance in laying hens with FLHS. Moreover, GEN treatment alleviated hepatic steatosis and lipid metabolism disorders through reducing the expression levels of mRNA related to fatty acid transport and synthesis and enhancing the mRNA expression levels of factors associated with fatty acid oxidation in FLHS layers, which may be achieved by activation of the G protein-coupled estrogen receptor­adenosine 5'-monophosphate (AMP)-activated protein kinase signaling pathways. These data not only provide compelling evidence for the protective effects and mechanisms of GEN against FLHS in laying hens but also provide the theoretical basis for GEN to alleviate other metabolic disorders in poultry.

Reduction in disialyl-T antigen levels in mice deficient for both St6galnac3 and St6galnac4 results in blood filling of lymph nodes.

Sialic acid (SA) is present at the terminal ends of carbohydrate chains in glycoproteins and glycolipids and is involved in various biological phenomena. The biological function of the disialyl-T (SAα2-3Galß1-3(SAα2-6)GalNAcα1-O-Ser/Thr) structure is largely unknown. To elucidate the role of disialyl-T structure and determine the key enzyme from the N-acetylgalactosaminide α2,6-sialyltransferase (St6galnac) family involved in its in vivo synthesis, we generated St6galnac3- and St6galnac4-deficient mice. Both single-knockout mice developed normally without any prominent phenotypic abnormalities. However, the St6galnac3::St6galnact4 double knockout (DKO) mice showed spontaneous hemorrhage of the lymph nodes (LN). To identify the cause of bleeding in the LN, we examined podoplanin, which modifies the disialyl-T structures. The protein expression of podoplanin in the LN of DKO mice was similar to that in wild-type mice. However, the reactivity of MALII lectin, which recognizes disialyl-T, in podoplanin immunoprecipitated from DKO LN was completely abolished. Moreover, the expression of vascular endothelial cadherin was reduced on the cell surface of high endothelial venule (HEV) in the LN, suggesting that hemorrhage was caused by the structural disruption of HEV. These results suggest that podoplanin possesses disialyl-T structure in mice LN and that both St6galnac3 and St6galnac4 are required for disialyl-T synthesis.

Pharmacist-guided pharmacogenetic service lowered warfarin-related hospitalizations.

Background: The authors aimed to assess outcomes with a pharmacogenetic (PGx)-informed, pharmacist-guided, personalized consult service for warfarin dosing. Methods: This retrospective cohort study included patients admitted with thromboembolic events. Eligible subjects received either PGx-informed (n = 389) or historical non-PGx pharmacist-guided warfarin dosing (Hx; n = 308) before hospital discharge. The composite of admission with bleeding or thromboembolic events over 90 days after the discharge was compared between the PGx and Hx groups. Results: The rate ratio (95% CI) of the composite of bleeding or thromboembolic admissions for PGx versus Hx was 0.32 (0.12-0.82). The estimated hazard ratio was 0.43 (0.16-1.12). Conclusion: A PGx-informed warfarin dosing service was associated with decreased bleeding and thromboembolic encounters.